Method of fabricating a terminal mechanism

ABSTRACT

The remote control assembly  10  is characterized by a terminal mechanism  34  including a tubular anchor member  36  slidably supported on a tubular fitting  22  extending from the conduit  14 . The anchor member  36  is secured to the outer end  30  of a rod  26  extending form the core element  12  and is disposed in close sliding relationship about the tubular fitting  22 . The terminal mechanism  34  also includes a tubular connector member  44  and a coil spring  46 . The connector member  44  is in telescoping relationship with the anchor member  36  and the spring  46  biases the connector member  44  in an extending direction yet for provides lost motion between the rod  26  and the control member in response to a predetermined collapsing force. A resilient cushion  48  is disposed in the connector member  44  for cushioning collapsing movement of the connector member  44  over the anchor member  36 . There is also disclosed a method of fabricating the terminal mechanism comprising the steps of sliding a rod end  38  of the tubular anchor member  36  into an open end of the tubular connector member  44 , establishing an abutment coacting between the connector member  44  and the anchor member  36  for limiting movement of the connector member  44  to a fully extended position in relationship to the anchor member  36 , placing a coil spring  46  about tile anchor member  36  and the connector member  44  to bias the connector member  44  to the fully extended position from the anchor member  36 , sliding the anchor member  36  over the tubular fitting  22  extending from the conduit  14 , and connecting the rod end  38  of the anchor member  36  to tile outer end  30  of the rod  26.

RELATED APPLICATION

This application is a divisional of application Ser. No. 09/218,396,filed Dec. 22, 1998 now abandoned, which is a divisional of Ser. No.08/909,314 filed Aug. 14, 1997 now U.S. Pat. No. 5,913,944.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject invention relates to a motion transmitting remote controlassembly of the type including a flexible motion transmitting coreelement movably supported in a conduit for transmitting motion in acurved path.

2. Description of the Prior Art

Remote control assemblies of this type are well known in the art to movea control member, such as a valve, from a conveniently located positionwhich is remotely located from the actual control member being operated.A known function in such control assemblies is the ability to compensatefor overtravel in the event the control member movement bottoms outbefore the core element movement. For example, if the control memberbeing moved by the core reaches the closed position and a sufficientforce is applied to the core element, the system could be damaged. Inorder to prevent such damage, an overtravel protection is built into theassembly to allow the core element to collapse when subjected to apredetermined high force. Examples of such assemblies are disclosed inU.S. Pat. No. 4,584,898 to Panushka; U.S. Pat. No. 4,630,957 toAusprung; U.S. Pat. No. 4,753,123 to Stormont; U.S. Pat. No. 4,799,400,to Pickell; U.S. Pat. No. 4,917,224 to Gokee; U.S. Pat. No. 5,058,462 toKilliany et al. and U.S. Pat. No. 5,613,405 to Kelley et al.

In the design of such assemblies, it is an objective to minimize thelength required by such overtravel mechanisms as well as to minimize thecomplexity of assembly.

SUMMARY OF THE INVENTION AND ADVANTAGES

A motion transmitting remote control assembly comprising a motiontransmitting core element supported for longitudinal movement in aconduit. A tubular fitting extends from one end of said conduit and arod is slidably disposed in the tubular fitting and has an inner endattached to the core element and an outer end extending from the tubularfitting. A terminal mechanism is attached to the outer end of the rodfor transmitting motion between the rod and a control member and forproviding lost motion between the rod and the control member in responseto a predetermined force acting between the rod and the control member.The assembly is characterized by the terminal mechanism including ananchor member slidably supported on the tubular fitting.

The invention also includes the method of fabricating the terminalmechanism comprising the steps of sliding the rod end of a tubularanchor member into an open end of the tubular connector member,establishing an abutment coacting between the connector member and theanchor member for limiting movement of the connector member to a fullyextended position in relationship to the anchor member, biasing theconnector member to the fully extended position from the anchor memberwith a predetermined force, sliding the anchor member over the tubularfitting extending from the conduit, and connecting the rod end of theanchor member to the outer end of the rod.

In accordance with the subject invention, therefore, there is provided aremote control assembly having overtravel protection in a minimum oflongitudinal space by overlapping the rigid tube extending from theconduit and an assembly which is relatively easy to assemble.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a side elevational view, partially broken away and in crosssection in the normal operating position; and

FIG. 2 is a view similar to FIG. 1 but showing the overtravel position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the Figures, wherein like numerals indicate like orcorresponding parts throughout the several views, a motion transmittingremote control assembly fabricated in accordance with the subjectinvention is generally shown at 10. As is well known in the art, themotion transmitting remote control assembly is of the type comprising aflexible motion transmitting core element, generally indicated at 12,slidably supported for longitudinal movement in a conduit, generallyindicated at 14. The core element 12 comprises a plurality of wirestrands wound together in a helical fashion with a wire filament 16wound spirally about the wire strands to define axial spacedconvolutions. The conduit 14 typically includes an inner tubularelement, frequently extruded plastic, surrounded by a compliment offilaments 18 which are bound by a flat wire 20 wrapped in spacedconvolutions about the filaments 18.

A first rod 26 is slidably disposed in the tubular fitting 22 and hascoupling 28 at an inner end attached to the core element 12 and an outerend 30 extending from the tubular fitting 22. A second rod 32 isslidably attached to the other end of the core element 12 and isslidably disposed in the fitting 24. The second rod 32 is threaded forconnection to a control member.

A tubular fitting 22 is connected to and extends from one end of theconduit 14. An equivalent fitting or ferrule 24 is attached to the otherend of the conduit 14.

However, a terminal mechanism, generally shown at 34, is attached to theouter end 30 of the first rod 26 for transmitting motion between the rod26 and a control member, not shown, and for providing lost motionbetween the rod 26 and the control member in response to a predeterminedforce acting between the rod 26 and the control member. The assembly 10is characterized by the terminal mechanism 34 including an anchor member36 slidably supported on the tubular fitting 22. The anchor member 36 istubular and has a rod end 38 secured to the outer end 30 of the rod 26and an anchor end 40 disposed in close sliding relationship about thetubular fitting 22. The rod end 38 of the anchor member 36 is secured tothe outer end 30 of the rod 26 by a pin 42 interconnecting the rod 26and the rod end 38 of the anchor member 36 to prevent relativelongitudinal movement therebetween. The pin 42 extends diametricallythrough the rod 34 and the anchor member 36 and may threadedly engageeither the rod 34 or the anchor member 36.

The terminal mechanism 34 includes a connector member 44 for connectionto a control member and a coil spring 46. The connector member 44 is intelescoping relationship with the anchor member 36 and the spring 46 isspirally disposed between the anchor end 40 of the anchor member 36 andthe connector member 44 for biasing the connector member 44 in anextending direction from the anchor member 36. A resilient cushion 48 isdisposed in the connector member 44 for cushioning collapsing movementof the connector member 44 over the anchor member 36.

A radially extending flange element, generally indicated at 50, isdisposed at the anchor end 40 of the anchor member 36 for abutting thespring 46. The flange element 50 includes a ring 52 extending annularlyabout the anchor member 36 and an annular disk 54 extending radiallyfrom the ring 52. The flange element 50 is an integral piece andseparate from the anchor member 36 and includes a fastener 56 forremovably securing the flange element 50 to the anchor member 36. Thefastener 56 is a screw threadedly engaging the disk 54 to frictionallyengage an axially extending groove in the outer surface of the anchormember 36, which prevents rotation of the flange element 50.

An abutment coacts between the connector member 44 and the anchor member36 for limiting movement of the connector member 44 in the extendingdirection from the anchor member 36 and is defined by a female shoulder58 extending radially inwardly on the connector member 44 and a maleshoulder 60 extending radially outwardly on the anchor member 36 withthe shoulders 58 and 60 being in radial overlapping relationship withone another.

The connector member 44 is tubular and extends between the abutment 58and 60 at an inner end to an open distal end 62. A link 64 extends intothe distal end 62 and a pin 66 extends diametrically through the distalend 62 and the link 64. The pin 66 is retained in place by a clip 68.The link 64 has center portion extending into the hollow of theconnector member 44 and an annular cup disposed about the end of theconnector member 44, with the pin 66 extending diametrically throughboth.

The invention also provides a method of fabricating a terminal mechanism34 for attachment to the outer end 30 of a rod 26 secured to a coreelement 12 slidably supported in a conduit 14 having a tubular fitting22 extending from one end of the conduit 14 in a motion transmittingassembly 10 for providing lost motion between the rod 26 and the controlmember in response to a predetermined force acting between the rod 26and the control member. The method comprising the steps of sliding a rodend 38 of a tubular anchor member 36 into an open end of a tubularconnector member 44, establishing an abutment coacting between theconnector member 44 and the anchor 36 for limiting movement of theconnector member 44 to a fully extended position in relationship to theanchor member 36, biasing the connector member 44 to the fully extendedposition from the anchor member 36 with the predetermined force, slidingthe anchor member 36 over the tubular fitting 22 extending from theconduit 14, and connecting the rod end 38 of the anchor member 36 to theouter end 30 of the rod 26. The biasing is further defined as placing acoil spring 46 about the anchor member 36 and the connector member 44.The method includes placing a flange element 50 on the anchor member 36to react with the spring 46 and connecting a link 64 to the open end ofthe connector member 44 to react with the spring 46 to bias theconnector member 44 to the fully extended position.

The method is further defined as first sliding the telescoping connector44 and anchor 36 members over the tubular fitting 22 to expose the rodend 38 of the anchor member 36 for connecting the rod end 38 of theanchor member 36 to the outer end 30 of the rod 26. In addition, theflange element 50 is positioned, by sliding, onto the tubular fitting 22along with the connector and anchor 36 members and is placed on theanchor member 36 after connecting the rod end 38 of the anchor member 36to the outer end 30 of the rod 26. In other words, the connector member44 is slid back onto the tubular fitting 22 to allow the pin 42 to beplaced in position. After the flange element 50 is secured to the anchorend 40 of the anchor member 36, the coil spring 46 is placed about theconnector and anchor 36 members. The link 64 is connected to the openend of the connector member 44 after placing the coil spring 46 aboutthe connector and anchor 36 members. In cases where used, a resilientcushion 48 is placed in the connector member 44 before attaching thelink 64 for cushioning collapsing movement of the connector member 44over the anchor member 36.

In operation, the link 64 is attached to a member to be controlled,i.e., moved, and that control member is moved in response to inputmovement from the second rod 32 at the other and remote end of theassembly 10. This movement is transmitted through the spring 46 duringnormal operation. However, in the event the control member, to which thelink 64 is attached, bottoms out or is otherwise prevented from moving,the spring 46 will collapse in response to a force of a predeterminedmagnitude. In other words, the spring 46 is quite strong enough totransmit normal forces between the rods 26 and 32 but will collapse orcompress under a predetermined force acting between the rods 26 and 32.

It is also possible to fabricate the assembly so that the distance theconnector member 44 can telescope onto the anchor member 36 is equal tothe stroke to the core element 12, which, in turn, may be determined bythe travel of the anchor member 36 on the tubular fitting 22.

The invention has been described in an illustrative manner, and it is tobe understood that the terminology which has been used is intended to bein the nature of words of description rather than of limitation.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims, whereinreference numerals are merely for convenience and are not to be in anyway limiting, the invention may be practiced otherwise than asspecifically described.

What is claimed is:
 1. A method of fabricating a terminal mechanism forattachment to the outer end (30) of a rod (26) secured to a core element(12) slidably supported in a conduit (14) having a tubular fitting (22)extending from one end of the conduit (14) in a motion transmittingassembly for providing lost motion between the rod (26) and a controlmember in response to a predetermined force acting between the rod (26)and the control member, said method comprising the steps of; sliding arod end (38) of a tubular anchor member (36) into an open end of atubular connector member (44), establishing an abutment coacting betweenthe connector member (44) and the anchor member (36) for limitingmovement of the connector member (44) to a fully extended position inrelationship to the anchor member (36), biasing the connector (44) tothe fully extended position from the anchor member (36) with thepredetermined force, sliding the anchor member (36) over the tubularfitting (22) extending from the conduit (14), and connecting the rod end(38) of the anchor member (36) to the outer end (30) of the rod (26). 2.A method as set forth in claim 1 wherein the biasing is further definedas placing a coil spring (46) about the anchor member (36) and theconnector member (44).
 3. A method as set forth in claim 2 includingplacing a flange element (50) on the anchor member (36) to react withthe spring (46).
 4. A method as set forth in claim 3 includingconnecting a link (64) to the open end of the connector member (44) toreact with the spring (46) to bias the connector member (44) to thefully extended position.
 5. A method as set forth in claim 4 furtherdefined as first sliding the telescoping connector and anchor (36)members over the tubular fitting (22) to expose the rod end (38) of theanchor member (36) for connecting the rod end (38) of the anchor member(36) to the outer end (30) of the rod (26).
 6. A method as set forth inclaim 5 further defined as sliding the flange element (50) onto thetubular fitting (22) along with the connector and anchor (36) membersand placing the flange element (50) on the anchor member (36) afterconnecting the rod end (38) of the anchor member (36) to the outer end(30) of the rod (26).
 7. A method as set forth in claim 6 furtherdefined as placing the coil spring (46) about the connector and anchor(36) members after placing the flange element (50) on the anchor member(36).
 8. A method as set forth in claim 7 further defined as connectingthe link (64) to the open end of the connector member (44) after placingthe coil spring (46) about the connector and anchor (36) members.
 9. Amethod as set forth in claim 4 including placing a resilient cushion(48) in the connector member (44) for cushioning collapsing movement ofthe connector member (44) over the anchor member (36).